User manual

page 17
Cyclon Series User Manual – General Description
6.3 Modulating Control (Optional)
In the ‘Modulating’ mode the opening and closing of
the suction regulator inlet valve is controlled by the
negative regulator. As the demand for compressed
air rises and falls, the valve modulates between
fully open and fully closed.
When the compressor is started and runs up to
load, the minimum pressure valve opens and air
under pressure passes from the separator vessel
into the user’s pipework. If the air pressure in the
user’s pipework is below the setting of the negative
regulator, the output signal from the negative
regulator will cause the suction regulator inlet valve
to open and the compressor will run on-load.
M
1
15
13 12
11
10
9
8
7
5
3
2
14
16
64
+-
Rising pressure in the separator vessel will cause
the output signal from the negative regulator to fall,
progressively closing the inlet valve to match air
flow to demand.
If the pressure in the user’s pipework rises above
the setting of the negative regulator and reaches
the upper set point, the controller de-energises the
unloader solenoid valve. The valve closes, shutting
off the regulation air supply to the suction regulator.
The suction regulator inlet valve closes and the
compressor runs in the off-load condition.
When the pressure in the user’s pipework falls to
the lower set point the compressor reverts to
running on-load.
1. Air Intake Filter
2. Suction Regulator
3. Venting Valve
4. Negative Regulator
5. Unloader Solenoid Valve
6. Shuttle Valve
7. Pressure Transmitter
8. Aftercooler
9. Minimum Pressure / Non-return Valve
10. Separator Filter
11. Pressure Relief Valve
12. Separator Vessel
13. Air-end
14. Drive Motor
15. Intake Pressure Switch
16. Air-end Discharge Temperature Sensor
REGULATION SYSTEM – MODULATING CONTROL